//交换两个整型变量的内容
void exchange(int* px, int* py)
//当不需要返回任何值时，函数返回类型就使用void。
{
	int z = 0;
	z = *px;
	*px = *py;
	*py = z;
}
 
int main()
{
	int integer1 = 0;
	int integer2 = 0;
	printf("Enter two integer to exchange the num:");
	scanf("%d %d", &integer1, &integer2);
	exchange(&integer1, &integer2);
	printf("the first integer entered:%d\n",integer1);
	printf("the second integer entered:%d\n",integer2);
	return 0;
}